1. Field of the Invention
The present invention relates to a tool mount for a machining apparatus.
2. Description of Prior Arts
FIG. 7 shows a representative example of tool mount for a machining apparatus. Specifically, spindle 1 has conical hollow 71 whereas cutting tool assembly E has conical projection 72. Conical projection 72 has grooved end 73. It is inserted in conical hollow 71 of spindle 1, and its grooved end 73 is caught by a collet (not shown). This arrangement has the advantageous effect of facilitating attachment of cutting tool assembly E to spindle 1.
This arrangement, however, requires careful constant checking of conical shape, and the use of a collet makes it difficult to assure the precise rotation of the tool. As for a machining apparatus which is capable of displacing a cutting tool such as a single-point tool C in a radial direction, an associated tool attachment requires that a tool is inserted deep in the spindle, and accordingly the tool slide of the tool attachment will be inevitably bulky.
In the hope of overcoming such disadvantage a contact type tool attachment as shown in FIG. 8 is proposed. It comprises tool slide 7 on the end of spindle 1 of a machining apparatus, and tool C is fixed by its base 74 to tool slide 7 with bolts 75.
This tool mount in which tool C is bolted to tool slide 7 advantageously assures machining precision. However, when tool C is changed, bolts 75 must be unscrewed one after another. This is a tedious work if conducted by hands. Otherwise, if an automatic tool changing system is used, it will be an extremely complicated system, which must be so designed and constructed that bolts 75 are unscrewed; a used tool is changed for a new one; and bolts 75 are screwed to fasten the new tool to tool slide 7. The time involved for the automatic changing work will increase with the number of different tools to be used one after another in machining. In this connection a machining apparatus equipped with such contact type tool attachment can be used in case that a single tool is used all the time or only in selected machining steps in which no frequent tool change is required.